This invention relates to vineyard trellis systems, and, more particularly, to a vine support system employing trellis wires supported on cross arms.
Growing and harvesting grapes and other similar vine crops tends to involve a great amount of care and labor. In addition to the usual necessities such as water and fertilizer, the vines must be trained on a trellis to support the grapes for proper growth, ripening, and harvesting. In addition, the vines must be pruned regularly and trained to intertwine with the trellis. Establishing a trellis system is a primary requirement for a vineyard, and the time and materials involved in setting up a trellis for each vine involves a large expenditure. Any measure that can reduce the cost of materials and labor in this regard comprises a useful advance over the prior art.
A typical vineyard arranged to be mechanically harvested will be planted so that there will be a plurality of parallel rows with spaced apart grape plants in each row. A trellis system is provided by installing a plurality of vertical posts spaced along each row, usually a post at each plant with an end post at each end of the row. One or more trellis wires are extended along each row, the wires supported by the vertical posts and anchored under tension to the end posts. The vines are grown along the trellis wires, the vines growing in a manner and at a height so that the grapes can be readily harvested therefrom.
One prior art method of attaching the trellis wires to the intermediate wooden posts has been by the use of simple staples. In vineyards that are not mechanically harvested, this is a rapid, inexpensive and effective way to form a trellis system. However, staples have been shown not to withstand the rigors of mechanical harvesting, particularly when the mechanical technique involves shaking the trellis to cause the grapes to fall. Shaking may pull the staples from the posts. Also, wooden stakes may not endure many years of exposure to the elements, and must be replaced periodically.
In recent years more sophisticated trellis systems have been introduced, using metal or plastic posts to carry the trellis wires. The posts may support various types of arms that are screwed or bolted to the posts to engage the trellis wires, or the trellis wires may be secured to the posts by twisted wire arrangements. Although these systems generally have proven to be more sturdy and durable than the older wooden grape stakes, their use typically involves more labor to install the support arms or twisted wire ties. One prior art system, described in U.S. Pat. No. 5,501,035, provides a trellis wire support that engages a standard T-post typically used as a fence post and the like. The trellis wire support extends about three sides of the post, and a wire clip is engaged with the trellis wire support to retain it on the post. The wire clip must be hooked on one side of the trellis wire support, extended to the opposed side, and bent closed to retain the assembly on the post. Although this procedure is not difficult, it requires several manual steps to complete, using pliers or similar tools. Considering the thousands of reiterations of this procedure necessary to complete an installation in a single vineyard, it is apparent that any measure that reduces the manual labor required for installation is economically advantageous.
There is an unmet need in the prior art for a vineyard trellis system that is simple and inexpensive to install while being strong enough to withstand mechanical harvesting and long-term exposure to the elements.
The present invention generally comprises an assembly for supporting trellis wires on standard metal fence posts or stakes. A salient feature of the assembly is that it requires no tools and very little labor to secure the assembly to the post.
In referring to standard metal fence posts, the typical post includes a T-shaped cross section formed of steel or the like, and a plurality of spines extending from the outer surface of the cross-web that defines the T shape. The spines typically have the form of a truncated triangular solid, and are spaced along the vertical extent of the cross-web.
The trellis wire support assembly of the invention includes a wire clip formed of steel wire or the like that is form-retaining and not bendable by manual effort. The wire clip includes opposed wire support arms, each comprised of a portion of the wire extending laterally and including a distal portion bent back over the lateral portion to define an acute angle therewith. The support arms extend in nominal vertical planes that are in disposed generally in angularly aligned relationship. The distal end of each bent portion is closely spaced to the support post to admit the trellis wire to the acute angle portion, and the trellis wire is captured within the acute angle.
A medial portion joins the two wire support arms. The medial portion consists of a V-shaped configuration extending in a nominal lateral plane. The apex of the V shape impinges on one edge of the cross-web of the post, and one leg of the V extends between two fence post spines.
The trellis wire support assembly further includes a cam over wire lock to secure the wire clip to the post. The cam over wire lock is comprised of a web formed of steel sheet or the like, extending laterally and having tapered opposed ends. In a first end a hole is placed to receive freely one end of the wire clip described above. (Alternatively, an L-shaped slot may be formed to receive the one end of the wire clip.) An R-shaped camming slot is formed in a second, opposed end of the cam over wire lock, and the spacing of the camming slot and the hole is slightly less that the spacing of the trellis wire support arms of the wire clip.
The assembly is installed by placing the trellis wire support clip in contact with the post, the opposed support arms extending upwardly and the V portion of the wire support impinging on one edge of the cross-web of the post, with one leg of the V portion extending between adjacent spines of the post at a desired height above the ground. One end of the trellis wire support clip is then passed through the hole in the cam over wire lock, and the wire lock is positioned to span the distance between the opposed wire support arms. The second end of the wire lock is urged into contact with the wire support clip, approximately at the junction of the wire support arm and the V portion. The oblique edge of the R-shaped slot and the junction portion of the wire clip are urged together by manual force, and the oblique edge acts like a cam surface to draw the junction portion into the slot against the resilient expansion force of the wire clip. When the junction portion fully inserted in the R slot, the resilient expansion force of the clip snaps the junction portion into the arcuate portion of the R shape, capturing the junction portion and securing the assembly to the post. No tools are required to complete this assembly. To remove the assembly, the two wire support arms may be grasped and brought together to release the resilient force on the R slot and permit the junction portion to be removed from the slot. The assembly is then free of the post, and may be removed.